Mononuclearly filled microcapsules

ABSTRACT

Described are mononuclearly filled seamless microcapsules comprising:  
     a capsule shell of a hardened capsule material based on an acid polysaccharide and  
     a filler material surrounded on all sides by the capsule shell, including an organoleptitic effective amount of a flavor,  
     wherein the microcapules is heat stable and/or cooking stable and/or deep fry stable and the water portion in the capsule shell is adjusted to a value of ≦50 wt. %, based upon the total mass of the capsule shell.

BACKGROUND OF THE INVENTION

[0001] 1. Field of Invention

[0002] The present invention concerns mononuclearly filledmicrocapsules, foodstuff compositions and other articles which includeone or more mononuclearly filled microcapsules as well as processes forproduction of mononuclearly filled microcapsules.

[0003] 2. Related Art of the Invention

[0004] In the field of encapsulation of active ingredients (activesubstances on or in carrier materials) there are frequently problems inparticular in the field of foodstuff technology, for example, theincomplete immobilization of the active substances on or, as the casemay be, in the carrier material.

[0005] In the field of the systems for functionalizing, in particularthe release (freeing) of active ingredients (active substances) from outof the carrier materials, these types of problems frequently result froman inappropriate, that is, either incomplete or however also possiblyearly or delayed, release of the active substance from out of itscarrier material.

[0006] Although in certain applications, in particular in pharmacology,agrarian chemicals and cosmetics, active substance-carrier materialcombinations have already been found, which meet the requirements bothwith respect to the encapsulation efficiency as well as with respect tothe requirements in practice regarding releasing, nevertheless in allindustrial nations great investment has been made in searching forsystems which in certain areas of application make possible asituation-appropriate release of active substances out of a carriermaterial.

[0007] Despite extensive efforts, until now only relatively fewfunctioning systems have been discovered for encapsulation andfunctionalizing of ingredients in the area of foodstuff technology andfoodstuff chemistry. This is due in part to the limited approval ofpossible carrier materials for the respective ingredients. In particularhowever problems occur with those types of flavors or fragrances, ofwhich the composition is complex, which is expressed in the diversity ofthe volatilities and the range of polarity of the individual aromacomponents of the fragrance or flavor as well as in the sensitivity ofone or more of the fragrance or flavor components to externalinfluences.

[0008] From the highly developed field of literature regarding activeingredient—release systems, reference can be made to the followingdocuments:

[0009] Brandau, Thorstein; Pharma+Food 3/2001, 8-12:

[0010] In this document microencapsulated active substances andmicrospheres are described in pharmaceutical and cosmetic applications.As processes for production of microspheres, the so-called microsphereprocess is specified, which results in highly spherical granules (solidspheres) with monomodal grain size distribution. The one or more activesubstance is evenly distributed throughout the entire sphere, in amatrix of the carrier material. Further, microcapsules are described,for the production of which a liquid or liquefied active substance isembedded in a solid shell.

[0011] WO 93/02785:

[0012] This document discloses a process for production of alginatespheres (solid spheres) from droplets of an alginate solution, whereindroplets are released from a nozzle and allowed to drop into an ionsolution, which solidifies them. The alginate solution is rendered intodroplets by oscillation excitation. Mononuclearly filled capsules arenot disclosed.

[0013] WO 98/15191:

[0014] This document discloses a process for production of spheres(beads) as nutrient—additives, wherein these solid spheres are loadedwith at least one active ingredient selected from the group of flavorsubstances. Mononuclearly filled capsules are not disclosed. Data orinformation regarding ingredients from the field of flavors orfragrances, in particular water insoluble flavors or fragrances, andtechnical advantages of the carrier material with respect to heatstability are disclosed, wherein however the release is not spontaneous,but rather occurs continuously during manufacture or preparation, inparticular however during storage of the nutrients.

[0015] WO 98/15192:

[0016] This document discloses a process for production of spheres(beads) as nutrient—additive, wherein in a finishing process steppreviously manufactured water insoluble spheres (solid balls) areretroactively or subsequently loaded with at least one active,amphiphilic ingredient.

[0017] The encapsulation of taste substances (flavor substances) inspheres (beads) brings about that the flavor substances possess animproved thermal stability and water insolubility during the furtherprocessing of the beads. The flavor release is however not instantaneousduring chewing or breaking of the bead-particles in the mouth, butrather is based upon a continuous and slow process of diffusion ofactive flavor components out of the encapsulated material into thefoodstuff matrix. This is described in particular in WO 98/15191 and inWO 98/15192.

[0018] EP 0 513 603 B1:

[0019] This document discloses a process for production of seamlesscapsules, in which a fluid stream is blown out of multiple nozzles forthe formation of capsules, so that droplets are formed, which are thenbrought into contact with a hardening fluid, in order to produce theseamless capsules. These seamless capsules are mononuclearly filled.Information regarding capsule materials is not provided. Informationregarding possible ingredients or possible technical advantages of theshell materials in practical applications are likewise not provided.

[0020] JP 11155480 A describes microcapsules filled with oily aromaticingredients, which are obtained by reaction of polysaccharides such asalginates with calcium or metal ions and which are heat and waterresistant. The shells of the described capsules exhibit however a highwater proportion of greater than 90 wt. %, based upon the capsule shell.

[0021] JP 09065853 A describes a microcapsule filled with the flavorsubstance wasabi which is formed with sodium alginate and apolysaccharide as form and stabilizing adjuvant by means of a two-fluidnozzle and is hardened with calcium chloride. However here the hardenedcapsule shell material possesses a very high water content, greatlyabove 50 wt. %.

[0022] A high water content in the capsule is very disadvantageous forthe performance of a capsule and in particular for its heat stabilityand its flavor retention value, as has been determined by variousexperiments within the framework of the present invention.

SUMMARY OF THE INVENTION

[0023] It is accordingly a primary task of the present invention toprovide a flavor release composition and a process for productionthereof, which is efficient with respect to the primary flavorencapsulation and which is universally employable as widely as possiblewith respect to the selection of the flavors to be encapsulated, thatis, in particular, not limited to a certain few oil soluble essences.

[0024] Beyond this, the process to be provided should preferably make itpossible to produce an at least substantially water insoluble flavorrelease system, with which the encapsulation of water soluble fillermaterials is also possible.

[0025] The system should further include or possess in its flavorrelease composition preferably instantaneous release characteristics,that is, a striking release of the flavor at the desired point in time,preferably during ingestion of the nutrients (burst effect).

[0026] At the same time the systems to be provided should be resistantto shear forces, preferably at least in such a degree, that they are notdisturbed by the shear forces occurring during the normal manufacture orpreparation of a foodstuff (nutrient preparation).

[0027] Beyond this, the flavor release system to be provided should beheat stable and/or cooking stable and/or deep fry stable (for thedefinition of these terms, see below).

[0028] In technical respects the process to be provided should makepossible a continuous production of a homogenous-shaped release system.

[0029] With respect to the flavor release system, the primary task issolved by provision of a mononuclearly filled seamless microcapsule,which comprises

[0030] a capsule shell of a hardened capsule material based on an acidpolysaccharide and

[0031] a filler material completely enclosed by the capsule shell,including or comprising an organoleptically effective amount of a flavor

[0032] wherein the microcapsule is heat stable and/or boiling or cookingstable and/or frying or deep fry stable and wherein the water proportionin the capsule is adjusted to a value of≦50 wt. %, based upon the totalmass of the capsule shell.

[0033] A mononuclearly filled seamless microcapsule is to be consideredheat stable when it maintains its structural integrity when immersed for15 minutes in a water bath at 50° C. Its structural integrity is moreparticularly said to be retained, when the filler material has notleaked from the microcapsule following the handling of the microcapsule.

[0034] A mononuclearly filled seamless microcapsule according to theinvention is considered boiling or cooking stable, when it maintains itsstructural integrity when subjected to 5 minutes in a water bath at 100°C. It structural integrity is verified particularly when the fillermaterial does not leak from the capsule following the treatment of themicrocapsule.

[0035] A mononuclearly filled seamless microcapsule according to theinvention is to be considered frying or deep fry stable when itsstructural integrity is maintained following subjecting to 5 minutes ina deep fry bath of molten palm oil at 180° C. It structural integrity isverified particularly when the filler material does not leak from thecapsule following the treatment of the microcapsule.

[0036] Among mononuclearly filled (micro) capsules there is to beunderstood, within the framework of the present disclosure, exclusivelysystems which possess a defined capsule (capsule shell, jacket), whichcompletely enclose a single (mono) core (nucleus) of filler material.Therein the layer of thickness of the capsule shell can be variable,preferably the core assumes the substantially larger proportion of thecapsule volume, in order to make possible a high loading of the capsule.The term or concept “mononuclearly filled microcapsule” is thus inparticular not applicable for “microspheres”, as they have described forexample in the above-mentioned article in Pharma+Food 3/2001. The justmentioned sphere—systems, in which the active ingredient is present inthe form of a finally divided imbedded emulsion or dispersion in thecarrier material, are accordingly usually referred to in the literatureas “polynuclear capsules”. A microcapsule in the sense of the presentdisclosure has a maximal volume of 65 mm³.

[0037] An inventive mononuclearly filled seamless microcapsule can beproduced in particular by a process with the following steps:

[0038] providing a liquid, organoleptically effective amount of aflavor-including filler-material for the microcapsules,

[0039] providing a preferably aqueous solution or dispersion of ahardenable capsule material based upon an acid polysaccharide,

[0040] forming discrete droplets of the liquid filler material for themicrocapsules and the solution or dispersion of the hardenable capsule(shell) material, so that the hardenable capsule material surrounds onall sides the liquid filler material in the droplets,

[0041] hardening the hardenable capsule (shell) material, so thatseamless polysaccharides are formed, which respectively surround thefiller material mononuclearly, and which are heat stable and/or cookingstable and/or deep fry stable,

[0042] drying the formed microcapsules, until the water content in thecapsule shell reaches a value of≦50 wt. %, based upon the total mass ofthe capsule shell.

[0043] Preferably a liquid filler material is produced, in that asolution or emulsion of the active flavor substances to be employed(which together produce the organoleptically effective amount of aflavor) is produced.

[0044] It is preferred to produce the discrete droplets of the liquidfiller material and the solution or dispersion of the hardenable capsulematerials in that the mentioned liquids are sent through a concentricmulti-nozzle arrangement. The discrete droplets then include at leasttwo different phases (filler material, capsule or ecapsulatingmaterial).

[0045] The hardening of the hardenable capsule material preferablyoccurs in that the hardenable capsule material, which in the formeddiscrete droplets surrounds on all sides the liquid filler material, iscontacted with an aqueous solution of multi-valent cations (for exampleCa-ions), whereupon the acid polysaccharides react with the cations inorder to form a seamless solid shell about the liquid filler material.

[0046] Following the hardening of the hardenable capsule material theformed capsules are separated from the employed multi-valent cationcontaining solution in conventional manner, and namely preferablyfollowing a very short contact between capsules and hardening bath.

[0047] The drying of the formed capsule shell occurs preferably at leastpartially by a water adsorption or absorption process, which in certaincases can be combined with other drying processes, for example aconvective air drying process.

[0048] Prior to drying, the capsules separated from the hardening bathare preferably also washed in order to remove any residual multi-valentcations from the capsules surface.

[0049] Further details regarding the design of the preferred process areset forth below.

[0050] The present invention is also concerned with articles orproducts, in particular foodstuff compositions, which include one ormore inventive mononuclearly filled microcapsules and a carrier materialfor the microcapsules (M).

[0051] Mononuclearly filled microcapsules which are suitable for humanconsumption are already known. Therein is to be distinguished (a)capsules which are producible by means of multiple nozzle technology,(b) cellular capsules, and (c) coacervation microcapsules.

[0052] Regarding capsules type (a) reference is made in particular tothe above comments regarding documents JP 11155480 and JP 09065853 A.

[0053] With respect to the capsule type (b), that is, the cell capsules,reference is made to the documents EP 242 135 A2 and EP 528 466 A1,which respectively disclose encapsulation of active substances in cellmaterial originating from microorganisms.

[0054] With respect to capsule type (c), that is, coacervationmicrocapsules, reference is made to the documents WO 93/19621 and WO93/19622.

[0055] The capsule types (b) and (c) or, as the case may be, thecorresponding processes for their production, possess certain advantagesand certain disadvantages. Disadvantageous are the conventionalmanufacturing processes for both capsule types still being batchprocesses, so that an economic capsule mass production is not possible.The preparation of suitable microorganism cells and the encapsulation insuch is besides this technically very demanding and highly liable toproblems, and the obtained cell capsules are besides this notparticularly stable against shear forces. The processes for productionof coacervation microcapsules, which are conventionally carried out withgelatin and an additive such as for example gum arabic, is only suitableunder the precondition that the flavor filling material to be surroundedis completely insoluble in an aqueous solution of the gelatin, whichresults in a commensurately large reduction with respect to thepotential complex flavors to be encapsulated. According to the documentsWO 93/19621 and WO 93/19622, the active components to be encapsulatedare limited to oil soluble components. Coacervation microcapsules arebesides this, as a rule, not heat stable, which further substantiallyreduces their employability.

[0056] In order to illustrate the enormous investment which is beingcarried out in the industry in order to compensate for theabove-described disadvantages of the above-described capsule systems andto produce heat stable active substance releasing systems with a high aspossible number of potential encapsulable flavors, reference is made tothe following documents:

[0057] U.S. Pat. No. 5,759,599

[0058] This document discloses a process for flavoring and production offoodstuffs by supplementation with flavor oil loaded capsules which arehardened by means of chemical cross-linking and thus more heat stable,which are produced by a coacervation process based upon a protein asshell forming material, and which during chewing are mechanicallyfractured. As discussed above, these capsules can only be loaded withoil soluble flavor substances.

[0059] WO 99/17871

[0060] This document discloses a process for encapsulation ofamphiphilic flavors in chemically cross-linked coacervationmicrocapsules, which on the basis of known distribution coefficients aredisadvantageously transported from outside into the core of apremanufactured non-flavored capsule, and there are dissolved untilreaching a defined equilibrium.

[0061] In contrast to the known types of mononuclearly filled capsules,the microcapsules according to the present invention are, in the case ofthe appropriate design of the manufacturing process, shear force stable,water insoluble, flavor and heat stable (capsules are not dissolvable inthe presence of water), without requiring that a supplemental chemicalcross-linking reaction be carried out. The inventive production processis significantly simpler than the production of cell capsules orcoacervation microcapsules and results also in significantly moreuniform microcapsule products. The inventive capsules can be produced bya continuous process and with substantially more constant dimensions. Incomparison with the microcapsules which are described in the documentsJP 11122480 A and JP 09065853 A, the inventive microcapsules arecharacterized in particular by an improved heat stability and animproved flavor retention.

[0062] The hardened microcapsule (shell) material of the inventivemicrocapsules comprise—as already described—preferably a substancepreferably hardened by contacting with mono-, di- or higher valuecations. In the inventive process it is thus preferred to employ anappropriate hardenable substance, which for this is preferably in theform of a solution. Preferred are substances which harden on contactwith Ca-ions, for example following dropping into a Ca-ion containingbath.

[0063] The capsule (shell) material for the microcapsules is inpreferable manner selected from the group comprising alginate, pectate,pectinate, carrageenan, gellan and their mixtures. The listed materialsare solidifible via cations and form in the hardened state particularlyheat stable and water insoluble capsules with a high shear stability.Suitable cations for hardening the listed materials are know to theperson of ordinary skill.

[0064] The inventive mononuclearly filled seamless microcapsules includein their filler materials an organoleptically effective amount of aflavor. This flavor includes preferably one or more flavor substances inthe sense of the European Union Flavor Guidelines 88/388/EWG, that is,one or more fragrance and flavor imparting substances which are presenteither naturally in consumables (for example in fruits) or are added toconsumables in order to impart thereto appropriate fragrance and taste.

[0065] It has been found to be particularly advantageous that theinventive employed flavor can possess ampliphilic characteristics andneed not be transported into the filler material by diffusion fromoutside following production of the capsule shell.

[0066] Within the framework of the present invention it is in generalimportant to employ measures which ensure that during the production nounacceptable amount of the flavor defuses out of the filler materialinto the capsule shell and in certain cases even out of this. This typeof measure includes for example the (rapid) separating of the capsulesfrom the hardening bath, the washing of the capsules and the drying ofthe capsules (see above). Frequently the inventive mononuclearly filledseamless microcapsules include as filler material a lipophilic solvent(for example a plant oil), in which a flavor is dissolved. In theproduction of the inventive microcapsules there is generally employedbesides this an aqueous solution of a hardenable capsule material. Thedistribution of a (for example amphiphilic) flavor substance between thefiller and the capsule material during the production of the inventivemicrocapsules can be described by the corresponding or appropriatedistribution coefficient. For reasons of providing a better overview ofthe invention it is however more convenient to provide, in place of thedistribution coefficient for the concentration equilibrium between thephase filler material and the capsule material, the distributioncoefficient between n-octanol and water, which in the literature areconventionally employed for characterizing substances. For a giventemperature (for example T=25° C.) the relationship of theconcentrations of a given flavor substance in the two phases n-octanoland water is constant; the distribution coefficient K_(o/w) is amaterial constant, just like the absorption logarithm of thedistribution coefficient logK_(o/w) (also characterized as logP_(o/w)).It is true that logK_(o/w) (=logP_(o/w))=log₁₀[C_(o)/C_(w)] with c_(o)=concentration of a flavor substance in n-octanol; C_(w)=concentrationof the same flavor substance in water.

[0067] For the purpose of the present invention the flavor substancescan be divided into three groups, depending upon their logK_(o/w) andnamely so, that each group is associated with a degree of difficulty forencapsulation of the respective flavor substance.

[0068] Flavor substances with a logK_(o/w)≧2 are lipophilic compounds,which are quite easy to encapsulate. An inventive microcapsule caninclude in the filler material (core) more than 50 and up to 95 wt. % offlavor substances with a logK_(o/w)≧2, based upon the total mass of thecapsule. In this first group of flavor substances there are substancessuch as carvone (logK_(o/w)=2.23), gamma-decalactone (logK_(o/w)=2.42),ethyl-caproate (logK_(o/w)=2.83), linalool (logK_(o/w)=3.28) andbeta-pinene (logK_(o/w)=4.37).

[0069] Flavor substances with a logK_(o/w) between 1 and 2 can beconsidered as ampliphilic compounds and are already more difficult toencapsulate. A microcapsule according to the invention can include inits filler material (core) at least 10 wt. % and up to 50 wt. % offlavor substances with a logK_(o/w) between 1 and 2, based upon thetotal mass of the capsule. In the second group of flavor substancesthere are substances such as ethyl butyrate (logK_(o/w)=1.77),benzaldehyde (logK_(o/w)=1.64), isoamyl alcohol (logK_(o/w)=1.28), ethylpropionate (logK_(o/w)=1.24) and diacetyl (butanedione)(logK_(o/w)=1.33).

[0070] Flavor substances with a logK_(o/w)≦1 are ampliphilic tohydrophilic substances and are particularly difficult to encapsulate. Amicrocapsule according to the invention can include in its fillermaterial at least 1 wt. % and up to 10 wt. % of flavor substances with alogK_(o/w)≦1, based upon the total mass of the capsule. In this thirdgroup of flavor substances there are substances such as ethyl lactate(logK_(o/w)=0.88), anisaldehyde (logK_(o/w)=0.95), butyric acid(logK_(o/w)=0.78), ethylacetate (logK_(o/w)=0.75).

[0071] For organoleptic reasons the flavor contained in dissolved ordispersed form in the filler material of the microcapsule according tothe invention usually contains at least 10 wt. %, based upon the totalmass of the flavor in the filler material, of one or more flavorsubstances with a logK_(o/w)<2. If the flavor is present in the fillermaterial in dissolved form, then the proportion of flavor substanceswith a logK_(o/w)<1 should however be maintained as small as possible inorder to prevent unacceptable flavor losses and preferably not more than1 wt. %, based upon the total mass of the flavor in the filler material.If the flavor in the filler material is in dispersed form, for examplean emulsified form, then the danger of a passage over of flavorsubstances into the capsule shell is reduced in comparison to adissolved flavor, so that also one or more flavor substances with alogP_(o/w)<1.0 can be contained in the flavor, for example in the rangeof 0.5-3.0 wt. % based upon the total mass of the flavor in the fillermaterial.

[0072] It becomes possible with the inventive process to producemononuclearly filled microcapsules in which several or all of thefollowing characteristics coexist:

[0073] 1. High retention of amphiphilic active substance components (inparticular flavor substances) in the core during the hardening anddrying of the shell material up until the finished end products;

[0074] 2. High stability of encapsulated active substance componentsduring storage;

[0075] 3. Low interaction between filler material and capsule material;

[0076] 4. High formal and/or mechanical and/or chemical stability of themicrocapsule relative to conditions as they exist conventionally duringthe further processing of microcapsules (for example mixing, frying,baking or cooking).

[0077] 5. Controlled but rapid release of the active substance containedin the filler material at the intended end-use of the microcapsules,that is, for example, during eating of a consumable which includesmicrocapsules filled with flavor substances.

[0078] For production of the filler material (for example, the core ofthe microcapsule), there is—as already described—usually first produced(a) a solution of the flavor substance to be incorporated in an oil or(b) a water-in-oil emulsion, which includes in its inner aqueous phasethe flavor substance. The term “oil” includes for the purposes of thisinvention both liquid plant oils as well as meltable plant or animalfats. As a rule it is advantageous to select an oil which readilydissolves the flavor substance to be taken up and at the same time issuitable for human consumption. In the case of employment ofwater-in-oil emulsions it can be advantageous to include emulsifiers inthe oil phase, which are suitable to stabilize the emulsion. By additionof a small amount of water, which preferably does not exceed 10 wt. %(based upon the liquid filler material) and a suitable emulsifier with aHLB-value (hydrophilic-lipophilic balance) of preferably less <5 withinthe filler material (core system) it becomes possible to produce astable water-in-oil emulsion. The emulsifiers are, for this purpose,preferably selected from the group consisting of mono-diglycerides,monoglycerides, polyglycerol esters, sorbitan esters and their mixtures.The production of the water-in-oil (w/o) emulsion within the fillermaterial (core phase) improves the retention of the water soluble flavorsubstance. The emulsifier can also be included in the oil phase in thesolution without addition of water. The emulsifier includes the morewater soluble flavor substance components within the liquid fillermaterial in the form of micelles.

[0079] Flavor substances which are solid at room temperature can bedispersed in liquid oil, wherein in certain cases dispersion aids can beadded.

[0080] For producing the solution or dispersion of a hardenable capsulematerial based upon an acid polysaccharide, in accordance with theinventive process conventionally the polysaccharide material, forexample the sodium salt of the alginic acid, is dissolved or dispersedin an aqueous solvent. Non-volatile, water soluble or water insolubledispersible substances can be added at this time, for example (a)glycerin, propyleneglycol or other agents for improving the mechanicalcharacteristics of the (dried) mononuclearly filled microcapsules to beproduced by plastifying of the capsule (shell) or (b) proteins and/orsaccharides for modification of the capsule composition.

[0081] In a preferred inventive process the solutions or dispersions ofthe hardenable capsule material and the liquid filler material are addedseparately from each other into a system, for example a multi-nozzlesystem, wherein the system is so designed, that discrete droplets areformed from the fluid filler material for the microcapsules and thesolution or dispersion of the hardenable capsule material for themicrocapsules, wherein the hardenable capsule material encloses orsurrounds the liquid filler material. Suitable double nozzle systems aredescribed in the literature, and for this reference is again made to thedocuments EP 0 513 603 B1 and WO 93/02785.

[0082] The said discrete droplets are comprised of an inner flavor core(filler material), which is enclosed on all sides by the outerpolysaccharide shell (capsule jacket). Core, shell and whole capsule arepreferably spherical. The core phase is preferably centered exactlywithin the capsule shell phase, which means, that the thickness of thecapsule shell at each point of the seamless microcapsule is the same. Adesign of this type contributes in great amount to a qualitatively highvalued capsule. The centering of the capsule core (filler material) canbe achieved by a suitable selection from the following parameters:relationship of the diameter of inner and outer nozzles; relationship ofthe flow-through rates through the inner and the outer nozzle; frequencyand amplitude of the optionally present vibrator for the multiplenozzles; intrinsic characteristics of the employed liquids (for fillermaterial and capsule (shell) material).

[0083] For hardening of the formed discrete droplets these areintroduced or dropped into a preferably aqueous or water-alcoholsolution of multi-valent cations. The selection of the multi-valentcations is adapted to or based on the type of the employed hardenablecapsule material. To the extent that calcium ions can be employed forhardening of an employed acidic polysaccharite, the solution ofmulti-valent cations preferably includes a dissolved calcium salt,wherein dissolved calcium chloride with a concentration in the range ofbetween 1 and 10 wt. % (based upon the total mass of the liquidhardening bath) is preferred. The solution of multi-valent cations isgenerally produced in that the corresponding salts are dissolved indeionized water or in tap water, to which a low molecular weight alcoholsuch as ethanol or isopropanal can be added, (a) in order to reduce thesurface tension of the solution and therewith to facilitate the emersionof the discrete droplets produced at the nozzle, (b) adjusting theconcentration the aqueous solution of the multi-valent cation containingsalt (for example calcium salt), and/or (c) to influence the gelling ofthe capsule material (for example alginate).

[0084] Alternatively to introducing or dripping the discrete dropletsinto a solution of multi-valent cations, the fine droplets can also besprayed with a solution of multi-valent cations.

[0085] As capsule materials, particularly suitable are alginate, that islinear co-polymers of -L-guluronate (G) and—D-mannuronate (M). Thealginate chain can be envisioned as a block co-polymer, comprised of“G-blocks” (homopolymer regions of guluronic acid residues), “M-blocks”(homopolymer regions of mannuronic acid residues) and “MG-blocks”(copolymer regions of mixed alternating sequences of M and G) ofvariable length. Alginates exhibit, besides a variable chemicalcomposition, also a broad molecular weight distribution, so that theconcept alginate is a generic term encompassing an entire family ofpolymers. The characteristics of each respective alginate depend on itsblock structure and its molecular weight.

[0086] Above a critical molecular weight the characteristics of analginate are essentially determined by its monomer composition and blockstructure. Generally, an increase of the content of guluronate leads toan increase in mechanically stable gels with elevated stability in thepresence of non-, or as the case may be, anti-gelling ions such assodium and magnesium as well as calcium complexing compounds; alginategels with a high guluronate proportion possess in general an elevatedporosity and tend during their gel formation only slightly towardssyneresis. In comparison thereto, alginate gels become softer and moreelastic by increasing the mannuronate proportion, and the correspondinggels shrink more strongly during their gel formation, which results in areduction in porosity.

[0087] For the encapsulation of active substances (in particular flavorsubstances) in principle all alginate types are suitable; those with amannuronate proportion above 40% are however preferred for theproduction of the microcapsules according to the invention for use infoodstuff applications, since they are comparatively elastic and exhibitsmall porosity, which has beneficial effects in flavor applicationssince they are comparatively elastic and exhibit low porosity, which isbeneficial for flavor use in applications in which heat and therewithflavor retention during the further processing have an impact. On theother hand, in the case that an intentional continued release of aflavor substance out of the inventive capsules under the influence ofheat, steam or air, is desired, that is, conditions as are presentfrequently in the case of tobacco products, guluronate rich alginateswith large pores are preferred. Due to their comparatively rapid gellinghigh molecular alginates are preferred for the encapsulation of flavorsubstances. For modulating the viscosity of an alginate gel it canhowever be of advantage to substitute high molecular alginates partiallywith low molecular alginates; the viscosity of an alginate gel isresponsible, besides other factors, for the size or magnitude of themicrocapsules formed in accordance with the inventive process and forthe capsule thickness (shell thickness). The viscosity of the alginategel has, besides this, a direct influence on the elasticity of theformed capsule.

[0088] For hardening (gelling) of alginate calcium ions are preferred,and this in particular due to their high effectiveness, the low costassociated with their employment, and their non-toxicity. Other divalentmetal ions such as those of zinc, copper, etc. can likewise be employed,likewise the ions of the di- or trivalent ions, aluminum, etc. Ascounter ions of calcium the salty and slightly bitter tasting chlorideis preferred for cost reasons; acetate and/or lactate are howeverpreferred for taste reasons. During the contacting of discrete droplets,which include alginate as the hardenable capsule material, with calciumions, a skin of insoluble alginate gel immediately forms. Subsequentlythereto, calcium ions slowly diffuse into the capsule shell. Fordroplets with a diameter of 100 to 5000 micrometers and an aqueoussolution of 1 to 10 wt. % calcium chloride the optimal contact time isless than 1 minute, it could however in certain cases be longer and forexample can be 100 minutes. If the flavor includes water solublecomponents, it is however of advantage to remove the formed capsulesalready after a short time out of the calcium bath, in order to preventthe transmission of water-soluble compounds into the bath, or at leastto maintain this within acceptable limits. It is to be noted that theloss of water soluble flavor components out of an alginate capsuleoccurs significantly more slowly than the loss of corresponding aromacomponents out of a comparable microsphere; these losses withmicrospheres are described in the document WO 98/15191. The abovecomments with regard to calcium ions and alginate apply in appropriatemanner to other pairings of an acid polysaccharide and mono- ormulti-valent cations.

[0089] Although the attention has been focused primarily in particularon the various types of alginate and thereunder again in particularsodium alginate, for the production of the capsules according to theinvention also other low esterified pectins or other acidpolysaccharides can be employed, in particular to produce waterinsoluble, heat stable gel capsules.

[0090] The concentration of the acid polysaccharide (hydrocolloid) inthe liquid mixture, from which the capsule (shell) is to be produced,lies preferably in the range of between 0.5 and 4 wt. %, based upon thetotal mass of the solution. Concentrated solutions are as a ruledifficult to process, since they have a high viscosity. Thepolysaccharide solutions can have additives such as locust bean gum,saccharose, glycerine or propylene glycol, in order to improve themechanical characteristics of the capsule (shell) material. Fillers suchas for example oligosaccharides, maltrodextrin, starches, gum arabic orcellulose derivatives (for example carboxymethyl cellulose) can bedissolved in the polysaccharide solution or be dispersed therein, inorder to improve the barrier characteristics of the capsules, in thatthey fill the pores, which would otherwise be present in the openstructure of the later formed gel.

[0091] The hardened capsules, or capsules in the process of hardening,can be separated from the suspension (capsules in ion containingsolution) for example by filtration or centrifugation. The result ismoist mononuclear filled microcapsules, to which can be added forexample an anti-caking agent, in order to maintain a free flowing(pourable) product. The still moist product can be dried underatmospheric pressure or reduced pressure, in order to produce a capsuleproduct with defined water content. In the same manner it becomespossible to adjust or tweak the mechanical stability of themicrocapsules.

[0092] The inventive capsules have a volume of up to 65 mm³; howeverparticularly in the field of flavoring technology significantly smallervolumes are preferred. Preferred volumes lie in the range of between4×10⁻⁶ m³ and 2×10⁻⁹ m³; these correspond in the case of preciselyspherical shaped microcapsules to a diameter of between approximately200 and approximately 1500 μm. Preferably, the volumes of themononuclearly filled microcapsules according to the present inventionlie in the range of between approximately 3×10⁻⁷ m³ and 3×10⁻⁵ m³; thiscorresponds in the case of spherical shaped microcapsules to a diameterin the range of approximately 400 to approximately 1200 μm.

[0093] The filler material for the inventive mononuclearly filledmicrocapsules contain flavor substances. The concept “flavoringsubstance” includes natural flavor substances, flavor substancesidentical to natural, artificial flavor substances, flavor extracts,reaction flavors and smoke flavors, according to EuropeanUnion-Flavor-Guidelines 88/388/EWG.

[0094] A large number of flavors and flavor ingredients can beencapsulated with the process according to the present invention. Theflavors include compounds such as menthol, natural extracts, essences,complex mixtures of extracts, essential (etheric) oils, oleo resins (amixture of an essential oil and a resin) or reconstituted natural, trueto natural or artificial flavors. The group of natural extracts,essences and oleo resins includes fruit essences, vanilla extract,paprika oleo resin, pepper oleo resin, cinnamon oil, oil of wintergreen,peppermint oil, bay or laurel oil, thyme oil, curled mint oil, cassiaoil, citrus oil and the like. The group of reconstituted natural,natural-like and artificial flavors include apple, cherry, strawberry,peach as well as sausage, cheese, tomato, celery and butter flavor.These flavors can be employed individually or as mixtures, according toknown processes. Depending upon their respective logK_(o/w) value theflavors and flavor ingredients can be incorporated in varying upperlimit amounts in the inventive capsules (see the above remarks regardingdegree of difficulty of encapsulation depending upon logK_(o/w)). Asparticularly advantageous, it is to be pointed out or emphasized thatalso slightly volatile and amphiphilic or as the case may be watersoluble flavor substances, as are key components for the reconstructionof fresh, fruity and plant notes, can be incorporated in sufficientlyhigh amount in the inventive capsules and can be maintained therein evenduring the further processing of the capsules.

[0095] Filled microcapsules in accordance with the present invention, ofwhich the filler material includes one or more flavor substances, areadapted for instant release of the flavor substance by mechanicalopening (fracturing) of the polysaccharide capsule. The capsule does notinterfere with eating. The person of ordinary skill would design thethickness and stability (rupture resistance) of the polysaccharidecapsule (shell) depending upon the requirements of the intendedemployment; he would for this in particular select a suitable hardenablecapsule material and employ plasticizers as necessary. In this manner itbecomes possible to produce for example inventive filled microcapsulesof which the filler material includes one or more flavor substances, andit can be incorporated for example in a foodstuff or consumable. Duringchewing of the foodstuff there would thus occur a spontaneous release ofthe flavor substance wherein, in contrast to the processes for flavoringof consumables known from the state of the art, none or onlyinsignificantly small amounts of flavor substance are retained by thematerial of the microcapsule.

[0096] The inventive microcapsules are formulated to be heat stableand/or boiling or cooking stable and/or frying or deep frying stable.These terms have the meanings described above and make it clear that themicrocapsules in accordance with the invention, in comparison to systemsknow in accordance with the state of the art, have a particularly goodflavor retention in semi-solid or sold foodstuff products duringcooking, baking, boiling, deep frying, frying, drying, extruding,microwave heating, etc. The microcapsules according to the inventionprotect the flavor substances contained therein in hot liquid productsvery well against decomposition and escape, and namely in particularduring pasteurizing and/or sterilizing of products into which they areincorporated.

[0097] The person of ordinary skill in this art is capable of modifyingor adapting the composition of many flavors in particular with respectto components of amphiphilic or hydrophilic nature to the capsulesystem, such that acceptable sensoric results can be achieved. In orderto guard against loss of active substances of the amphiphilic orhydrophilic components characteristic for the respective flavor duringhardening and drying of the capsules, the inventive process when usingthe conventional nozzle system, as described for example in EP 0 513 603B1, or WO 93/02785 and the therein cited documents, is preferably sodesigned, that (a) the hardenable capsule material first comes intocontact at the tip of the nozzle with the active substance contained inthe filler material selected from the group of flavor substances and (b)during or as the case may be following the hardening of the hardenablecapsule material the one or more aroma substances are not, or as littleas possible, defused into the capsule surrounding the filler material.The person of ordinary skill is capable based on tests to determinesuitable process parameters on the basis of the known or predictabledistribution coefficients, which prevent or at least reduce thetransition of flavor substances into the capsule material and beyondthis into the hardening bath or the atmosphere.

[0098] It is possible for the person or ordinary skill to have in mind,at least essentially, the composition of the flavor contained in thefiller material and the organoleptic profile thereof. Components such asfor example isoamyl acetate (logP_(o/w)=2.12), ethyl butyrate(logP_(o/w)=1.73) and benzaldehyde (logP_(o/w)=1.64), which areamphiphilic in nature and of which the water solubility significantlyincreases in this sequence, represent the respective characteristics oras the case may be typical components for banana, pineapple and cherryflavor. Production conditions targeted to conserve these flavors make itpossible for the person of ordinary skill, within the framework of thepresent invention, to achieve an almost complete retention orpreservation of these flavor substances in the dried microcapsules inaccordance with the invention.

[0099] The retention of flavor substances such as isoamyl alcohol, ofwhich the logP_(o/w) of 1.22 means a renewed elevation of the watersolubility in comparison to the three above-mentioned substances, ismaintained at least within acceptable boundaries using processconditions targeted thereto in accordance with the invention, whilenon-adapted manufacturing conditions would practically lead toquantitative losses.

[0100] Acetealdehyde, which is responsible for the fresh characteristicof various fruit flavors, has a logP_(o/w) of −0.16 compared to isoamylalcohol and thereby exhibits yet again a significantly increased watersolubility. Quantitative losses of this flavor substance can occurduring hardening and drying if it was contained in dissolved form in thefiller material.

[0101] Even retention of highly water soluble substances such asacetaldehyde can however be significantly increased by appropriatemeasures, in order also to retain within the core of the capsule thesensoric activity, for example by dispersion of solid flavor substancesor simply water in oil emulsions, micellular systems or liposomes in acase of liquid flavors.

[0102] For applications which require heat processing of the finalfoodstuff, there are preferred in accordance with the inventionfree-flowing (pourable) microcapsules, dry on their outer side, with awater proportion of ≦50 wt. % in the capsule shell based upon the massof the capsule shell, in comparison to capsules with a water proportionin the capsule shell of ≧50 Wt. %. In the case that the water proportionis ≧50 wt. %, flavor substances can escape from the microcapsule in theheat along with the then surplus or excess free water steaming out ofthe microcapsule. Dry capsules, for example calcium hardened capsuleswith a water content of ≦50 wt. % in the capsule shell, based upon thetotal mass of the capsule shell, can be hydrated only with difficulty,so that even a heat exposure in the presence of water does notimmediately result in disruption of the active substance releasingsystem; this would be different in certain cases were the inventivecapsules to have a higher water proportion of, for example ≧50 wt. % inthe capsule shell, and also in microspheres known according to the stateof the art, which include flavors embedded in a matrix, which whenheated in the presence of water are less stable than the preferredinventive microcapsules, which have a water proportion of ≦50 wt. % inthe capsule shell; in the case of capsules with a filler materialproportion of 80 wt. % and a capsule shell proportion of 20 wt. %,respectively, based upon the total mass of the capsule, the waterproportion corresponds to less than 10 wt. % based upon the total massof the capsule.

[0103] According to a preferred process design two-phase discretedroplets are dripped into a hardening bath, wherein the impacting of thedroplets is cushioned or reduced to the extent possible, in orderfollowing hardening of the capsule (shell) material to produce acentered core (of filler material). The person of ordinary skill in theart would, in order to accomplish this, reduce the distance between themulti-nozzle system and the hardening bath and/or would in a first stepspray the discrete droplets with the hardening solution while they arestill falling, before the droplets submerge in the hardening bath and/orwould modify the amplitude and frequency of a conventional vibratorassociated with the multi-nozzle system and/or would adapt the intrinsiccharacteristics of the capsule shell and liquid core phase and/or woulduse certain overflow funnel systems or channel systems and/or wouldemploy tension reducing compounds in the hardening bath, which wouldproduce a foam upon the surface of the hardening bath or would reducethe surface tension of the hardening bath.

[0104] The polysaccharide solution forms a solid skin about the corematerial (filler material) immediately upon contact with themulti-valent cations. Thereafter the cations slowly diffuse out of thehardening bath (the hardening spray) into the internal of the capsuleshell, so that a hardening gradient forms, wherein at the outer side ofthe capsule shell a comparatively high hardness and on the inner side ofthe capsule shell a comparatively low hardness exists (see also below).The person of ordinary skill would determine on the basis of tests atwhich point in time in the hardening process the gelled microcapsulesare to be removed from the hardening bath.

[0105] If amphiphilic flavor substances are employed, it is to beexpected that the hydrophilic compounds within a flavor substancemixture would be those which would be first to diffuse out of the corephase (filler material phase) into the aqueous polysaccharide solution,while the discrete droplets following exiting the multi-nozzle jet arejust forming, and in a second step diffuse through the capsule shellwhich is in the stage or process of hardening and diffuse in thedirection towards the hardening bath. The droplet forming and thehardening steps are thus preferably carried out in the shortest possibletime in accordance with the invention. It is known that polysaccharidesolutions based upon alginate, gellan or pectin, in contact withmulti-valent cations such as for example calcium, form an inhomogeneousstructure. The cations attach initially only to the outer surface of theouter polysaccharide phase of the mentioned discrete droplets anddiffuse subsequently towards the center wherein they develop a so-calledgel gradient. The capsule shell strength is thus greater on the outersurface of the already formed microcapsule than inside, and in the innerpart of the gel phase this is liquid or of soft consistency. Themolecular chains of the hardening hydrocolloid are contracting, whereinsimultaneously a certain amount of water is pressed or extruded out ofthe gel. This phenomenon is known as the syneresis effect, and theshorter the gel time, the smaller the syneresis effect. Depending uponfactors such as gel time, the polysaccharide solution concentration, andthe cation solution concentration, the syneresis can make a differenceof between 5 wt. % and 60 wt. %, based upon the mass of the originalliquid droplet. A certain amount of hydrophilic flavor substance canescape in this manner (by syneresis) and along with the accompanyingwater be transported into the hardening bath. According to a preferredembodiment of the present invention the gellation time, that is, thecontact time between the formed polysaccharide phase of the capsule andthe bath with multi-valent cations, is reduced to a minimal value, whichpreferably is less than 1 minute and in particular in the range ofbetween 5 and 30 seconds. The inhomogeneity of the formed gel and thereduced syneresis effect attenuate the migration of the saturatedhydrophilic flavor substance out of the core phase (filler material)through said gel phase into the hardening bath. This is an importantpoint of distinction in comparison to the above described microcapsuleswhich are produced by coascervation and of which the contact timebetween the forming microcapsules and the aqueous reaction bath is inthe realm of hours or even days.

[0106] The isolation or removal of the formed microcapsules out of thehardening bath is preferably carried out continuously, and namelypreferably by means of a sieve technique or by centrifugation. At thetime point of separation from the hardening bath the microcapsules arein a wet state. The water content of the moist microcapsules liesbetween 50 and 90 wt. %, based upon the total mass of the particle. Thewater exists both as water bound to the polysaccharide as well as freewater within the porous structure of the polysaccharide gel, and asinterstitial water between the formed microcapsules. The water stillcontains a not insignificant concentration of multi-valent cations.According to a preferred embodiment, following separation of the moist(wet) microcapsules from the solution of multi-valent cations (hardeningbath) a washing step is carried out. For this, a washing solution isemployed, which is preferably comprised of deionized water, however maybe a mixture of water and an organic solvent such as for example ethanolor isopropanol. The washing step is preferably integrated into theseparating step, wherein a spray nozzle for application of a washingsolution is incorporated in the separating device employed forseparating. In this manner the multi-valent ions, which are stillpresent in the interstitial water of the microcapsules and in the outerpart of the polysaccharide gel, can be rapidly washed out. This preventsa further diffusion of the reactive multi-valent cations into thepolysaccharide gel and prevents thus also a further syneresis effect.Microcapsules which are subjected to a process with a short gelling timecan still loose up to 50 wt. % on the basis of the syneresis effect, inthe case that the microcapsules are left standing unwashed followingseparation from the hardening bath.

[0107] Due to the tendency of the hydrophilic flavor substances to exitout of the inner phase (core; filler material) of the moistmicrocapsules through the porous polysaccharide gel structure of thecapsules (shell) material, in accordance with a preferred embodiment ofthe present invention the still moist microcapsules are converted asrapidly as possible into the dry form. The drying process leads thereto,that the porous shell structure of the microcapsules further contractsuntil a point at which even the hydrophilic flavor substances can hardlydiffuse through the dried capsule shell matrix. The drying can either becarried out in a batch or continuously, wherein however a continuousprocess design is preferred, in order to shorten the time span betweenthe above described washing of the moist microcapsules and the dryingstep. Each standing time of the moist microcapsules can lead to afurther syneresis and therewith to a further transport of hydrophilicflavor substances out of the microcapsules.

[0108] In the framework of the present invention the conventional dryingprocesses can be employed, for example with use of conductive dryers(such as standard ovens or vacuum ovens) or convective dryers (forexample whirlwind dryers with rotating dryer). These techniques arehowever suited when primarily or even almost exclusively lipophilic andnon-volatile flavor substances are contained in the filler material(core). When, in comparison, water soluble or slightly volatile flavorsubstances are to be encapsulated, then an important part of thesematerials can vaporize with a simply water evaporation, an effect, whichis critical in particular in the case of convective drying processes, inwhich a particularly high proportion of flavor substances can be removedfrom the filler material, since vaporizable substances are continuouslytransported away via the air stream. In a preferred design of thepresent invention the said drying techniques are employed in a predryingstep, in which the water content of the capsule shell material remainshigh and therewith the sympathetic (i.e., along with the water)evaporation of hydrophilic flavor substances remains tolerable oracceptable. Wet microcapsules frequently have a water content, whichlies between 96 wt. % and 65 wt. %, based upon the total mass of thecapsule shell material. With the pre-drying preferably less than 25% ofthe total water to be removed is evaporated. In such a manner flavorsubstances with a logK_(o/w)<2, in particular logK_(o/w)<1.5 areparticularly effectively encapsuled.

[0109] According to a further alternative embodiment of the presentinvention a drying technique is employed, in which the preferably washedmoist microcapsules or the saturated dried microcapsules are contactedwith a water adsorbing or water bonding substance. As water absorbing orwater bonding substance, preferably an organic salt such as for examplemagnesium carbonate, magnesium sulfate, calcium chloride, is employed,or compounds such as silicon dioxide, zeolite or starch. Preferred inmany cases is a silicon dioxide, which preferably has an internalspecific surface area of 150 m²/g or more. The water up-take capacity ofsuch a silicon dioxide (also referred to as silica) should be greaterthan 100% and preferably above 200%, based upon its own mass. First thestill moist or predried microcapsules are conventionally homogenouslymixed with up to 50 wt. % and preferably approximately 25 wt. % of thesaid silica. For mixing, a drum mixer, spiral mixer, paddle mixer orplow share mixer can be employed. Following a mixing time, which shouldnot exceed 10 minutes and is preferably approximately 5 minutes, themicrocapsules are separated from the loaded water adsorbing or bondingsubstance using a sieve technique. For this, vibrating or rotatingsieves can be employed. The mixing and sieving can either be carried outin a batch or as a continuous process. The capsule shell material of thedried microcapsules has a water content of maximally 50 wt. %, basedupon the mass of the capsule shell. The advantage of such a dryingprocess in comparison to the above mentioned standard drying techniquesis in particular in (a) a shorter process time, (b) the absence of aflavor substance emission in the air, (c) the good flow ability of thedried microcapsules even with high flavor loading and, in particular,(d) in the improvement with respect to the water soluble and volatileflavor substance component or proportion. Flavor substance with alogK_(w/o)<2 and in particular logK_(w/o)<1.5 are significantly betterencapsulated than when using the conventional drying techniques. Theimprovement with respect to the retention can be as much as 50 to 90 wt.% based upon the starting mass of the employed flavor components in thefilling material, see Example 10.

[0110] The inventive microcapsules have a water proportion in thecapsule shell of ≦50 wt. %, based upon the total mass of the capsuleshell. A substantial reason therefore is that internal research hasshown that microcapsules with a higher water proportion in the capsuleshell lose an unacceptable high proportion of their highly volatile andtheir water soluble flavor substances when they are heated within theirfoodstuff matrix. The more water soluble and volatile compounds areentrained in the evaporating water and transported out of themicrocapsules, so that this can be referred to as co-distillation. Thethermal stability of the inventive microcapsules with a water content of≦50 wt. % in the capsules shell is based not alone on its physicalintegrity, on the basis of its water insolubility, and its irreversiblegel formation. It is based also and not least thereupon, that the flavorprofile of the original encapsulated flavor system is conserved inunchanged formal composition. An inventive microcapsules with a fillermaterial, which has a proportion of at least 80 wt. %, based upon thetotal mass of the dried capsule, and of which the capsule shell materialis accordingly a proportion of at most 20 wt. %, should generally have awater content of not more than 10 wt. %, again based upon the total massof the dried microcapsules. In the case of a filler material proportionof 90 wt. % the water content should not be above 5 wt. %.

[0111] The invention is described in greater detail in the following onthe basis of examples.

EXAMPLE 1

[0112] Process for producing inventive (standardized) capsules for usein Examples 2 through 50.

[0113] Sodium alginate (type Protonal LF20/60), FMC BioPolymer, Drammen,Norway) was dissolved in demineralized (deionized) water with stirring(15.0 g alginate for 1000 ml water), until a clear solution is produced.The stirring time at a water temperature of 8-15° C. was approximately30 minutes. The solution was allowed to rest at least 3 to 5 hours priorto processing in order to obtain the desired viscosity of maximally 200mPa·s, better yet since the previous day; solutions which are older than24 hours are no longer usable. After the stirring process the pH of thesolution was measured and in certain cases set to pH 6.5-7.5 with base.Tank A was filled with this solution.

[0114] A selected flavor concentration or an essence was mixed withneutral oil (for example Miglyol, CONDEA Chemie GmbH, Witten, Germany)or a commercially available plaint oil (for example soy bean oil) forproducing a solution or dispersion with a defined degree of dilution;this dilute flavor solution was supplied to Tank B and continuouslystirred to avoid demixing. Both solutions were separately pumped viapressure lines to a conventional double nozzle system which wasvibrating, wherein the flavor solution was supplied to the internalnozzle with a diameter of 200 micrometer, the alginate solution wassupplied to the outer nozzle with a diameter of 1000 micrometer. Theflow rate relationship of the two solutions was controlled using twoseparate pressure lines in such a manner that the relationship of theliquid A:B of 10:1 was achieved.

[0115] Standard parameters:

[0116] Internal nozzle 0.3 bar/flow-through 14.0=330 g flavor per hour

[0117] Outer nozzle 0.5 bar/flow-through 20.0=3300 g alginate per hour

[0118] Frequency=160 Hz, amplitude=4.8

[0119] Therewith, a two-phase liquid droplet with an average particlediameter of approximately 2.2 mm was obtained with a weight relationshipof shell to core of 10:1. By gelling with 10% calcium chloride solutionthese droplets were gelled during 5 minutes (solution of 10 g anhydrouscalcium chloride in 100 g demineralized water).

[0120] Due to syneresis during the gelling of the alginate, one obtaineda moist capsule with a diameter of approximately 1.6 mm, with flavorcore diameter remaining unchanged. The particles are isolated byfiltration and briefly washed with tap water for removal of surpluscalcium ions. The filtered and washed particles are dried in a fluidizedbed with an air temperature of 50° C. and an air amount of 10 m³/min,wherein the average particle diameter of the particles dried by means ofthis standard drying method was reduced to 1050 micrometer. Forsupporting the fluidizing of the wet and, at this time, also stickycapsules, 1% magnesium carbonate was added as flow aid material. Theaverage particle diameter, which could most easily be measured by lightmicroscopy and for which a statically significant member of capsules wasdetermined, exhibited a model distribution, the capsule diameter wasdetermined to be 1050±100 micrometer. Alternatively a laser bendingmethod (Malvern) was employed for particle size and particledistribution measurement.

[0121] The resulting dry standard capsules exhibited on average a coreportion of a 80 wt. % and a shell portion of 20 wt. %, wherein the shellhad an average residual water content of 50%, as determined using adrying process with a halogen dryer.

[0122] The dilution of the flavor concentrate with oil in the core ofthe capsule was so selected, that in comparative tests with use of aflavoring by means of (a) the corresponding liquid flavor concentrate or(b) a spray dried form, in use the same mass proportion of flavor wasrespectively employed. Therein care was taken that in the flavorizingwith capsules, respectively, a dosing was adjusted or set at between 0.2and 2.0 wt. % capsules, depending upon the end use and the desiredrelease rate, in order to obtain a uniform image. The (comparative)flavorization by means of liquid flavor concentrate occurred accordingthereto on a basis of the employed dilution of the corresponding flavorconcentrate in capsules and the supplemental dilution by encapsulationof the shell portion of partial dried alginate gel. In the employment ofvarying capsule sizes the changed dilution and dosing were givenappropriate consideration.

[0123] This type of capsule product was employed in the followingexamples.

EXAMPLE 2

[0124] Chewing gum was produced in accordance with the followingformulation.

[0125] Formulation type: chewing gum, sugarfree TABLE 1 Chewing Mass RawMaterial/ Additive Ingredient Wt.-% 01 Chewing Gum Base 27.62 02 Xylitol9.87 03 Sorbitol 48.59 04 Mannitol 11.54 05 Glycerin 2.16 06 Aspartam0.11 07 Acesulfam K 0.11 100.0 Wt.-% (based upon the total mass of thechewing Flavoring: mass) 08a Capsules - Peppermint Oil 1.0* 08bCapsules - Peppermint Oil 2.0** 08c Peppermint Oil 0.64

[0126] Production Method

[0127] a—mixing of 1, 2, 3, 4, 5, 6, 7.

[0128] b—kneading the mass at a temperature of 50° C. until mixture ishomogeneous.

[0129] c—addition of flavor (0.64% ingredient 08c or as the case may be1.0% ingredient 08a or as case may be 2.0% ingredient 08b) based uponchewing gum mass (total mass of ingredients 1 through 7).

[0130] d—laminating the mass

[0131] e—cutting into strips

[0132] The chewing gum strips were evaluated for fragrance (aroma bysniffing) and taste (chewing gum in the mouth). The result of theorganoleptic tests (6 test persons) represented in Table 2 showed thatthe encapsulated aroma with both capsule sizes exhibited significantlyhigher intensity in comparison to the liquid aroma with the same massproportion. TABLE 2 Intensity of Particle the Aroma Size (mm) OlfactoryOral Alginate capsule 1.050 5.25 7.00 (additive 08a) Alginate capsule0.800 6.38 8.40 (additive 08b) Non-Encapsulated 4.50 4.70 (additive 08c)

EXAMPLE 3 Baking

[0133] Biscuits (cracker) were produced in accordance with followingformula.

[0134] Formula type: snack biscuit, cheese, salted TABLE 3 Additive RawMaterial/Ingredient Wt.-% 01 Wheat Flour (Cracker type) 66.530 02Vegetable Shortening 7.980 03 Raw Sugar 1.550 04 Inverted Sugar Syrup1.550 05 Salt 1.150 06 Ammonium Bicarbonate 0.890 07 Malt Syrup Extract0.806 08 Sodim Monophosphate 0.665 09 Sodium Bicarbonate 0.550 10 CitricAcid 0.066 11 Bacterial Protease 0.027 12 Sodium Metabisulfite 0.016 13Water 19.370 100.0 Wt.-% (based upon the total Flavorization: mass otthe additives 1-13) 14a Capsules - Cheese flavor 1.0* 14b Capsules -Cheese Flavor 2.0** 14c Cheese Flavor, top note, liquid 0.08

[0135] Production Method

[0136] a—mixing 2, 3, 4, 5 and 13 (70° C.), until all components aredissolved.

[0137] b—addition of ingredients 1 and 6-12 to the dough, addition

[0138] of flavor 14a or as the case may be 14b or as the case may be14c.

[0139] c—mixing for approximately 10 minutes, until the dough is flat

[0140] d—storing the dough for 2 hours

[0141] e—laminating the dough and cutting to size

[0142] f—addition of granulated salt on the cracker dough (optional)

[0143] g—baking for 4 minutes in an oven at 185° C. (at the beginningthe temperature should be 210° C.). Injection of steam while thecrackers are introduced into the oven, this injection being carried outso long until the temperature reaches 190° C.

[0144] h—during removal of the crackers vegetable fat is sprayed on thecrackers (optional), until the crackers have achieved a certainshininess.

[0145] The crackers were evaluated for fragrance (aroma by sniffing) andtaste (cracker in the mouth). The results of the organoleptic testing (7test persons), presented in Table 4, showed that that the encapsulatedaroma of both capsule sizes exhibited a significantly higher intensityin comparison to the liquid aroma with the same mass proportion. TABLE 4Intensity of Particle the Aroma Size (mm) Olfactory Oral Alginatecapsule 1.100 5.40 7.00 (additive 14a) Alginate capsule 0.900 5.80 8.40(additive 14b) Non-Encapsulated 4.50 3.88 (additive 14c)

EXAMPLE 4 Deep Frying

[0146] A panade (for bread crumb encrusted product) was produced inaccordance with the following formula:

[0147] Recipe Type: Wet Panade TABLE 5 Additive Ingredients Wt.-% 01Chicken breast in pieces, 76.0 approximately 15 g 02 Salt 1.00 03 Wetpanade, BAB 137* 5.80 04 Water 10.2 05 Dried panade, Panko 102* 7.00100.0 Wt.-% (based upon the Flavorizing: total mass of additives 1-5)06a Flavor, carrot, liquid 0.16 06b Flavor, carrot, capsules 1.0**

[0148] Production Method

[0149] a—wet panade (03) and salt (02) dispersed in water, allowed toswell

[0150] b—flavor (06a or 06b) is dispersed in the swollen wet panadedescribed in a)

[0151] c—meat is added to the flavorized wet panade

[0152] d—allowing to drip, and rolling in dry panade (05)

[0153] e—deep frying the panaded meat pieces in vegetable fat,approximately 180° C., approximately 4 minutes.

[0154] The deep fried chicken breast pieces were sampled for fragrance(aroma by smelling) and taste. TABLE 6 Application: Chicken NuggetsFlavor: Carrot Aroma- Taste Profile Dosing # Type Profile 1 Profile 2Profile 3 In Wt.-% 06a Liquid Weak Slightly Weakly 0.16 Flavor CarrotCabbage Green 06b Capsule Typical Sweet Cabbagy 1.0 Carrot

EXAMPLE 5 Steaming, Deep Frying

[0155] The noodles were produced in accordance with the followingformula.

[0156] Formula type: Instant, Asiatic TABLE 7 Additive Ingredient Gram01 Wheat flour 1000 02 Water 250 03 Salt 13 04 MSG 1.2 05 Kansui*** 1.206 Guar Gum 0.4 1265 .8 Wt.-% (based upon the Flavorizing: total mass ofingredients 1-6) 07a Leek aroma, capsules  1.0%* 07b Leek aroma, spheres  1.0%** 07c Leek aroma, spraydried Product (20 parts flavor, 80 PartsMaltodextrin/ Gum Arabicum) 0.25% *correspondes to a leek flavor portionof 0.05% - corresponding to 0.25% of the corresponding spraydriedproduct - with an adjusted capsule size of 1050 micrometer and a flavordilution by oil in the core of 5:95%. **corresponds to a leek flavorportion of 0.05% - corresponding to 0.25% of the correspondingspraydried product - at an adjusted sphere size of 500 micrometer and anembedded flavor content of 5%. **alkali solution (imparts to the noodlesa fresh, light tingling sour taste) comprised of: 05a calcium carbonate0.96 05b sodium carbonate 0.12 05c sodium polyphosphate 0.12

[0157] Production Method

[0158] a—mixing and pressing: ingredients 01-07 are blended in a doughkneader. The result is a crumbly mass, which is pressed together on aplate with a noodle wood (roller).

[0159] b—5 minutes allowing to rest

[0160] c—rolling out the dough: a dough plate was extruded ever thinnerusing a domestic noodle machine between two rollers, maximal 1.1 mm.

[0161] d—cutting the noodles (the extruded dough plate was pressedbetween two rippled rollers on a perforated sheet in fine noodle rods.

[0162] e—steaming (the whole sheet with the noodles were cooked in asteamer for 3 minutes at approximately 4 bar at 100-110° C. not fullycooked (instant characteristic of the noodles)

[0163] f—deep frying

[0164] g—the noodles were deep fried for 50 seconds in hot palm oil at155-160° C. Subsequently the surplus oil was allowed to drip off, thenoodles were cooled and packed—by deep frying the noodles became morecrunchy, more flavorful and more durable and storage stable.

[0165] The noodles were evaluated for fragrance (aroma by sniffing) andtaste (in the mouth). The results of the organoleptic testing (7 testpersons) are presented in Table 8, and show that the encapsulatedflavor, in comparison to the spray-dried flavor at the same dose, alwayshad a significant preceptibility and recognizability, while thespray-dried flavor and the flavor encapsulated in spheres practicallywas no longer recognizable. TABLE 8 Non-Encapsulated Capsules Spheres*Spraydried Product After Onion, Weaker than Slightly-like Pressinggreen, capsules leek, extremely clearly-like weak leeks Following Green,leek, Too weak Lightly oniony, Cutting weaker than weak dough sampleFollowing Light leek, Too weak Too weak steaming green weak howeverrecognizable Finished Slightly Too weak Too weak Noodles like leek

EXAMPLE 6 Drying with Silicon Dioxide

[0166] 15 g sodium alginate (type Protanal LF20/60, FMC Biopolymer) weredissolved in 985 g demineralized water using a high speed kneading mixerof the type Ultra-Turrax until the aqueous solution became clear. Thealginate solution was prepared several hours prior to its use, in orderto enable a complete hydration of the alginate chains. 2 g leek flavorconcentrate were dissolved in 98 g neutral oil (type Miglyol, CONDEAChemie GmbH). The two solutions were separately supplied by means ofgear wheel pumps out of two supply tanks to a vibrating two-streamnozzle head. The nozzle head system included an inner nozzle with 150 μmdiameter and an outer nozzle with 1000 μm diameter. The flow rate of thetwo solutions was so adjusted that it formed a laminator flow out of thenozzle, 400 g per hour flavor solution (leek) through the inner nozzleand 2800 g per hour alginate solution through the outer nozzle. Thevibration thereof was so adjusted that it interrupted the stream andformed homogeneous discrete droplets. At a frequency of 130 Hz two-phasedroplets of approximately 2 mm diameter were formed. The droplets fellinto a 10% calcium chloride reaction bath, so that immediately a solidlayer formed around the liquid filler material. The calcium bath reactorwas comprised of a pipe system, through which the calcium chloridesolution flowed and so continuously transported the fresh gelledcapsules to a separator. The flow rate of the pump for the calciumchloride solution was adjusted to a gelling time of approximately 1minute. The gelled capsules were transported through a pipe reactor andthen separated on an 800 μm sieve. The sieved capsules were washed withtap water. The wet capsules had, due to syneresis which occurred duringthe gelling step, a diameter of only approximately 1.6 mm, with a watercontent of the shell material of 98%. 520 g of wet capsules wet capsuleswere obtained and these were mixed for 10 minutes with 260 g silicondioxide (Sipernat S50, Degussa) and then separated from the silicondioxide on a vibrating 800 μm round sieve. 120 g dried capsules with aparticle size of 1.2 mm were produced. The water content of the shellmaterial of the dried capsules was 49%. The dried microcapsulesincluded, at a total 83 wt. % liquid filler material, a water content of8.4 wt. %.

EXAMPLE 7 Predrying plus drying with silicon dioxide

[0167] 15 g sodium alginate (type Protanal FL 20/60, FMC Biopolymer)were dissolved in 975 g demineralized water using a high speed kneadingmixer of the type Ultra-Turrax. 50 g strawberry flavor and 1 gpolyglycerol ester (type PGRP 90, Danisco Cultor) were dissolved in 39 gneutral oil, 10 g tap water were added, then slowly mixed forapproximately 5 minutes and subsequently homogenized for 1 minute with ahigh speed kneading mixer of the type Ultra-Turrax in order to produce astable water-in-oil emulsion. The two solutions were supplied to avibrating two-stream nozzle head with an inner diameter of 150 μm and anouter diameter of 1000 μm. The flow rates were adjusted for the flavorsolution to 300 g per hour and for the shell solution to 3000 g perhour, the vibration frequency to 180 Hz. Two-phase droplets ofapproximately 1.8 mm diameter were formed. The droplets fell in a 10%calcium chloride reaction bath. The flow rate of the pump for thecalcium chloride reaction bath was adjusted to a gelling time ofapproximately 1 minute. The gelled capsules were separated on a 800 μmsieve and washed. The wet capsules had a diameter of 1.7 mm and a watercontent of the shell material of 97%. 605 g wet capsules were obtainedand pre-dried for purposes of pre-drying in a fluidized bed dryer (typeSTREA 1, aromatic) with an air flow of 100 m³ per hour and an inlettemperature of 50° C. for approximately 10 minutes. 490 g pre-driedcapsules were obtained, mixed with 200 g silicon dioxide (Sipernate S50,Degussa) for approximately 5 minutes and then separated on a vibrating800 μm round sieve. 140 g dried capsules with a particle size of 1.1 mmwere produced. The water content of the shell material was 49%. Thetotal microcapsule included 79.1% liquid filler material, the watercontent was 10.2%.

EXAMPLE 8 Drying with Silicon Dioxide

[0168] 15 g sodium alginate (type Protanal LF 20/60, FMC Biopolymer) and10 g gellan gum (type Kelcogel, Kalco) were dissolved in 975 gdemineralized water using a high speed kneading mixer of the typeUltra-Turrax. 500 g of a peppermint flavor solution was prepared. Thetwo solutions were supplied to a vibrating two-stream nozzle head withan internal diameter of 200 μm and an outer diameter of 500 μm. The flowrates were adjusted to 500 g per hour flavor solution and 800 g per hourshell solution, the vibration frequency was adjusted to 200 Hz.Two-phase droplets of approximately of 1.4 μm diameter were formed. Thedroplets fell into a pipe reactor with 5% calcium chloride solution. Theflow rate of the pump for the calcium chloride reaction bath wasadjusted to a gel time of approximately 10 seconds. The gelled capsuleswere separated on an 800 μm sieve and washed. The wet gel capsules had adiameter of 1.2 mm and a water content of the shell material of 96.5%.The objected 1100 g wet capsules were mixed with 275 g silicon dioxide(Sipernat S50, Degussa) for approximately 10 minutes and then wereseparated for the silicon dioxide on a vibrating 800 μm round sieve. Anamount of 540 g dried capsules with a particle size of 0.9 mm wereproduced. The water content of the shell material was 4.6%. The totalmicrocapsule comprised 93.1% liquid filler material, the water contentwas 3.2%.

EXAMPLE 9 Continuous Gelling Process; Short Gel Time

[0169] This example served to demonstrate the improvement which can beachieved with reference to the flavor component encapsulation inalginate microcapsules when the gelling process is carried out as acontinuous 1 minute process, in comparison to the encapsulationtechniques carried out as a batch process, in which the gelled capsulesremain in contact with the gel bath for hours.

[0170] 50 g sodium alginate were dissolved in 195 g demineralized waterusing a high speed kneading mixer of the type Ultra-Turrax. 250 gModel-flavor were dissolved in 750 g neutral oil. The Model flavor wascomprised of flavor components, which cover a large spectrum ofwater/oil solubility as indicated by logK,/w -values, see the followingTable 9. TABLE 9 Component Amount % (w/w) Log K_(o/w) Anisyl alcohol 50.95 Ethylpropionate 5 1.24 Benzaldehyde 5 1.64 Isoamylacetate 5 2.12Ethylcaprylate 5 3.9

[0171] The two solutions (alginate, flavor) were conveyed to a vibratingtwo-stream nozzle head with an inner diameter of 150 μm and an outerdiameter of 500 μm. The flow rates were adjusted for the flavor solutionto 500 g per hour and for the shell solution to 1000 g per hour, thevibration frequency was adjusted to 200 Hz.

[0172] For the preferred short continuous gelling process the formeddiscrete droplets fell into a pipe reactor, which was filled with 5%calcium chloride, and were so transported, that the dwell time was 1minute. The resulting wet capsules were sieved and washed with tapwater.

[0173] The results of the 1 minute capsule production (corresponding to8.3 g encapsulated flavor solution) were then dissolved in 200 ml 1%aqueous sodium chloride solution. The mixture was then extracted for 4hours in a perforator with diethyl ether. The diethyl ether extract wasanalyzed using HRGC/MS. The results were evaluated based on the surfaceof the GC/MS peaks for the components per gram of encapsulated aromasolution.

[0174] For the batch gelled process the formed discrete droplets fellinto a 5% calcium chloride containing reactor with a dwell time of 2hours. The formed wet capsules were thereafter sieved and washed withtap water. The same analytical protocol was carried out as for the shortgel time process.

[0175] 10 g Model-flavor solution were dispersed in 200 ml 1% aqueoussodium citrate solution. The mixture was extracted in a perforator for 4hours with diethyl ether and evaluated as described above.

[0176] The flavor retention for the respective flavor components duringthe short continuous gelling process and the long gel batch process werecalculated on the basis of the amount of the Model-flavor solution whichoriginally flowed through the nozzle system and theoretically wasencapsulated, the results are presented in Table 10. TABLE 10 FlavorRetention: Short Gel Time Long Gel Time Components (continuous) (Batch)Anisyl alcohol 60%  6% Ethylpropionate 61%  0% Benzaldehyde 82% 11%Isoamylacetate 80% 18.5%   Ethylcaprylate 90% 90%

[0177] In the process with short gel time the flavor retention of thesubstances with a logK_(o/w)<3.9 was significantly better than in theprocess with longer gel time.

Example 10 Comparison of various drying processes

[0178] This example served to demonstrate the differences with regard toflavor retention which exist between conventional convective dryingprocessing (fluidized bed dryer) and the drying process using wateradsorbing substances.

[0179] A sample of the wet capsule product, produced according to theprocess with short gel time as described in Example 4, was dividedfollowing washing into two equal batches of 200 g.

[0180] The first batch was dried by addition of 100 g silicon dioxide tothe wet capsules. The substances were mixed for 10 minutes and the thendried capsules were subsequently manually separated from silicon dioxideon an 800 μm-sieve. 60 g dried capsules were obtained. The water contentof the shell material of the dried capsules was 45% (corresponding to 7%water content and 84.2% liquid filler material based upon the mass ofthe total capsules).

[0181] The second 200 g batch was dried in a fluidized bed dryer (typeSTREA 1, Aeromatic) at 30° C. in the temperature and 100 m³ per hour airflow, in order to obtain an amount of dried capsules of 60 g. The watercontent of the shell material of the dried capsules was 62%(corresponding to 14.4% water content and 76.8% liquid filler materialbased upon the mass of the total capsule).

[0182] The varying amounts of liquid filler material, which were foundin the two dried capsule types, show already the difference with regardto the flavor retention, which are associated with the two dryingprocesses. The silicon dioxide dried capsules had 50.52 g (84.2%) liquidfiller material, those capsules dried in the fluidized bed had incomparison only 46.08 g (76.8%) liquid filler material.

[0183] The details of the retention of each flavor component is shown inthe following Table 11. The used analytical method was identical withthat described in Example 9. TABLE 11 Drying “water adsorbing”Substances: Convective Drying: % Retention % Retention Anisyl alcohol33%  5% Ethylpropionate 50%  4% Benzaldehyde 80% 52% Isoamylacetate 95%60% Ethylcaprylate  0% 65%

EXAMPLE 11 Influence of the Water Content in the Shell on Heat Stability

[0184] This example underscores the importance of the water contentpresent within the shell material of the dried capsule in order toachieve an efficient heat stability of the encapsulated flavor during aheating process.

[0185] Capsules with cheese flavor were added to a cracker dough andthen baked. The capsules had various water content (various degrees ofdrying). The flavor dosing was maintained constant for all tests.

[0186] The crackers were prepared according to the following formula(Table 12): TABLE 12 Additive Amount (%) 1 Vegetable Fat 7.98 2Industrial Sugar 1.55 3 Fructose Syrup 1.55 4 Salt 1.15 5 Wheat Flour66.53 (cracker type) 6 Ammonium bicarbonate 0.89 7 Malt extract syrup0.806 8 Sodium Monophosphate 0.665 9 Sodium Bicarbonate 0.55 10 CitricAcid 0.066 11 Bacterial Protease 0.027 12 Sodium Metabisulfite 0.016 13Water 19.37

[0187] The crackers were evaluated by a sensory test group sons) withregard to the oral flavor intensity. The ion scale ranged from 1-5:

[0188] 0 no taste

[0189] 1 very weak flavor note, almost not recognizable

[0190] 2 flavor note is too weak

[0191] 3 acceptable taste note

[0192] 4 good and strong taste note

[0193] 5 too strong taste note

[0194] The results are summarized in Table 13. TABLE 13 MassRelationship Mass Mass Capsule Water/Capsule Relationship RelationshipSensory Type Shell Capsule/Cracker Flavor/Cracker Evaluation Wet   95%3.5% 0.04% 1 Lightly   91% 2.7% 0.04% 1 Dried Medium 66.7% 1.3% 0.04% 2Dried Dried 38.9%   1% 0.04% 4

[0195] The dried capsules clearly impart on the basis of their heatstability the best sensory results.

EXAMPLE 12 Effect of Varying Aroma Application Designs

[0196] This example shows the varying sensory evaluations of leekflavor, which was applied to crackers in liquid form, in stray driedform and in encapsulated form.

[0197] The crackers were prepared as described in Example 6 and baked,however at 200° C. for 4 minutes. The sensory evaluation of the 3varying flavor embodiments summarized in Table 14 are based upon thesame definition of scale as in Example 11. TABLE 14 Mass Relationship(Flavor and Carrier) for Mass Flavor Example Relationship Sensory TypeCapsule/Cracker Flavor/Cracker Evaluation Liquid 3.5% 0.04% 1 SprayDried 2.7% 0.04% 2 Capsule 1.3% 0.04% 4

[0198] The leek flavor encapsulated in alginate capsules showed the bestresults in regard to the baking stability, compared with the standardflavor embodiments in liquid or, as the case may be, spray dried form.

1. Mononuclearly filled seamless microcapsule, including: a capsuleshell of a hardened capsule material based on an acid polysaccharide anda filler material surrounded on all sides by the capsule shell,including an organoleptitic effective amount of a flavor, wherein themicrocapules are heat stable and/or cook stable and/or deep fry stableand the water portion in the capsule shell is adjusted to a value of ≦50wt. %, based upon the total mass of the capsule shell.
 2. Mononuclearlyfilled microcapsules according to claim 1, wherein the hardened capsulematerial for the microcapsules includes a substance hardened bycontacting with mono-, di- or higher valent cations.
 3. Mononuclearlyfilled microcapsules according to one of the preceding claims, whereinthe hardened capsule material for the microcapsules is selected from thegroup consisting of alginate, pectate, pectinate, carrageenan, gellanand mixtures thereof.
 4. Mononuclearly filled microcapsules according toone of the preceding claims, wherein the flavor contained in the fillermaterial includes at least 10 wt. %, based upon the total mass of theflavor in the filler material, of one or more flavor substances with alogK_(w/o)<2.
 5. Mononuclearly filled microcapsules according to one ofthe preceding claims, wherein the flavor contained in the fillermaterial includes at least 10 wt. %, based upon the total mass of theflavor in the filler material, of one or more flavor substances forwhich the following applies: 1<logK_(o/w)<2.
 6. Mononuclearly filledmicrocapsules according to one of the preceding claims 1-4, wherein theflavor contained in the filler material includes at least 10 wt. %,based upon the total mass of the flavor in the filler material, of oneor more flavor substances for which the following applies: logK_(o/w)<1.7. Foodstuff preparation, including: one or more mononuclearly filledmicrocapsules according to one of the preceding claims and a carriermaterial for the microcapsule(s).
 8. Process for producing mononuclearlyfilled microcapsules according one of claims 1-6, with the followingsteps: preparing a liquid organoleptically effective amount of aflavor-including filler material for the microcapsules, preparing apreferably aqueous solution or dispersion of a hardenable capsulematerial based on acid polysaccharide, forming discrete droplets of theliquid filler material for the microcapsules and the solution ordispersion of the hardenable capsule shell material, so that thehardenable capsule material surrounds on all sides the liquid fillermaterial in the droplets, hardening the hardenable capsule shellmaterial, so that seamless polysaccharide capsules are formed, whichrespectively include mononuclearly filled material and are heat stableand/or cook stable and/or deep fry stable, drying the formed capsuleshells, until the water content in the capsule shell reaches a value of<50 wt. %, based upon the total mass of the capsule shell
 9. Processaccording to claim 8, wherein the seamless polysaccharide capsules arecontacted with a water adsorbing or water binding substance for dryingthe formed capsules.
 10. Process according to one of claims 8 through 9,wherein the hardenable capsule shell material are hardenable by contactwith multi-valent cations, wherein the discrete droplets are contactedwith a solution for hardening the hardenable capsule material, whichcontains the multi-valent cations.
 11. Process according to one ofclaims 8-10, wherein the discrete droplets are contacted for maximally 1minute with a solution for hardening the hardenable capsule shellmaterial, which solution contains the multi-valent cations.
 12. Processaccording to one of claims 10 or 11, wherein the formed seamlesspolysaccharide capsules are washed prior to the step of drying theformed capsule shells, in order to remove multi-valent cations from thecapsule surface.